Antistatic shelf for electronic circuit boards

Abstract

An adjustable antistatic shelf is provided for supporting electronic circuit boards in a storage cabinet. The shelf includes a base having parallel planar top and bottom surfaces. A plurality of parallel rail pairs extends outwardly from the top surface of the base, the rails in each pair spaced apart to form a groove of a first width, with adjacent rail pairs spaced from each other to form grooves of a second width. A complementary plurality of rail pairs extends outwardly from the bottom surface of the base in alignment with the rail pairs extending from the top surface. Tabs extend from the shelf for adjustably mounting the shelf to tracks in a storage cabinet. The shelf is molded as a unit from a conductive plastic.

What is claimed is: 
     
       1. An antistatic shelf for adjustably supporting electronic circuit boards in a storage cabinet or the like comprising: a base having parallel planar top and bottom surfaces;   a plurality of parallel grooves disposed in said top surface, a first set of said grooves having a relatively narrow width and a second set of said grooves having a relatively wide width;   a complementary plurality of parallel grooves disposed in said bottom surface extending in the same direction and in alignment with the grooves in said top surface, individual grooves in the bottom surface having a width correspnding to that of the groove aligned therewith on the top surface; and   means for adjustably mounting said base in a storage cabinet;   said base and grooves molded as a unit from a conductive plastic.   
     
     
       2. The shelf of claim 1 wherein said base is square or rectangular and said mounting means comprises: a tab integrally molded at each corner of said base and;   mechanical fastener means for attaching said tabs to corresponding tracks in a storage cabinet.   
     
     
       3. The shelf of claim 2 wherein said tabs each include an opening and said fastener means comprises a threaded fastener inserted through the opening of each tab and threaded into a rotatable backing plate adapted to be inserted and rotated in an opening in a corresponding track for engagement with opposed walls of said track, whereby said tabs and backing plates can form clamps upon rotation of said backing plate in said track for mounting the shelf to storage cabinet tracks by clamping corresponding tracks between tabs and backing plates upon tightening of said threaded fasteners. 
     
     
       4. The shelf of claim 2 wherein said base has a front edge, a rear edge, and opposed side edges perpendicular to said front and rear edges; and a lip extending upwardly from said rear edge beyond said top surface to prevent a circuit board supported on the base from being pushed beyond said rear edge.   
     
     
       5. The shelf of claim 4 wherein the tabs integrally molded at the front corners of said base extend from said side edges to maximize access to said base along the front edge thereof. 
     
     
       6. The shelf of claim 5 wherein the tabs integrally molded at the rear corners of said base extend from the rear edge thereof, and are perpendicular to the front tabs. 
     
     
       7. The shelf of claim 1 wherein said conductive plastic comprises injection-molded structural polyethylene. 
     
     
       8. The shelf of claim 1 wherein said relatively narrow and relatively wide grooves are disposed on said top surface in an alternating pattern with corresponding alternating relatively narrow and wide grooves on said bottom surface. 
     
     
       9. The shelf of claim 1 wherein said grooves are formed from a plurality of parallel rails extending outwardly from said top and bottom surfaces. 
     
     
       10. The shelf of claim 9 wherein said rails are arranged in pairs defining said relatively narrow width, with the spacing between adjacent pairs defining said relatively wide width, whereby said grooves are formed in an alternating relatively narrow and relatively wide pattern.